From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Wed, 16 Nov 2022 17:29:34 +0000 (-0500)
Subject: vma_merge: Set vma iterator to correct position.
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1f9e8d47327728d4d206cae9832ef8843627f4f5;p=users%2Fjedix%2Flinux-maple.git

vma_merge: Set vma iterator to correct position.

When merging the previous value, set the vma iterator to the previous
slot.  Don't use the vma iterator to get the next/prev so that it is in
the correct position for a write.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---

diff --git a/mm/mmap.c b/mm/mmap.c
index cf4620d2040b..bfb23049a07b 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -992,6 +992,7 @@ struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm,
 		    && can_vma_merge_after(prev, vm_flags, anon_vma, file,
 				   pgoff, vm_userfaultfd_ctx, anon_name)) {
 			merge_prev = true;
+			vma_prev(vmi);
 		}
 	}
 	/* Can we merge the successor? */
@@ -1083,9 +1084,6 @@ struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm,
 	validate_mm(mm);
 	khugepaged_enter_vma(res, vm_flags);
 
-	if (res)
-		vma_iter_set(vmi, end);
-
 	return res;
 }